File storage cabinets are used for filing documents and are generally of the vertical and lateral type. Such file cabinets usually include a number of file drawers vertically stacked with each file cabinet being moveable from within the cabinet housing to an extended open position to provide access to the drawer space.
If more than one drawer is moved to the open position at the same time, the file cabinet assembly has tendency to tip forward in the opening direction of the drawers. In other words, the center of gravity of the cabinet is shifted sufficiently forward that the entire assembly becomes unstable and can dangerously fall forward.
Many mechanisms have been developed to overcome this tipping problem by preventing more than one drawer from being opened at a time. U.S. Pat. No. 4,772,028, issued Sep. 20, 1988 in the name of Steven M. Boyer, and assigned to the assignee of the subject invention, discloses a drawer interlocking means for storage cabinets. Such a storage unit includes a vertical member extending on a first side of the storage units for locking all of the storage units at a time and opening the same. Included on a second side of the storage units is a blocking member which prevents opening movement from the closed position of all but one of the storage units. A mechanical key element unlocks the locking member allowing access to the storage units and opening of one storage unit when unlocked.
It is desirable to utilize an electronic storage interlocking system rather than a single key. Electronic opening assemblies have been known in single door opening systems wherein electronics codes may be applied to allow unlatching of a door. Such systems are disclosed in U.S. Pat. No. 4,083,424 to von den Stemmen et al, and U.S. Pat. No. 3,812,403 to Gartner, and U.S. Pat. No. 3,831,408 to Featherman, and PCT application PCT/AU87/00014 in the name of Blake.